Given f (x)= 4 (1 – x), what is the value of f(-3)?

N76 [4]

1
A coefficient is the number attached to a variable (k). In front of k is an implied 1 because k*1=k. So the coefficient of the third terms is 1

8 0

2 years ago

Find the length of each side.

34kurt

Answer:

16.852

Step-by-step explanation:

All side lengths are the same in an octagon. What you do is take the diamater and multiply it by 0.383. Diamater is the radius doubled.

7 0

3 years ago

In which situation is the distance traveled proportional to time? A car moving in stop-and-go traffic A person biking on a trail

Sindrei [870]

For this case, what you must do is to see in which scenario the speed of keeping constant during a certain time.
"A person biking on a trail at 1212 miles per hour for 2020 minutes"
We observe that the distance in this case is proportional to the time and the constant of proportionality is the speed.
In other words:
d = v * t
Answer:
the distance traveled is proportional to time in:
"A person biking on a trail at 1212 miles per hour for 2020 minutes"

5 0

3 years ago

<img src="https://tex.z-dn.net/?f=%5Csf%20%5Clim_%7Bx%20%5Cto%20%5Cinfty%7D%20%5Ccfrac%7B%5Csqrt%7Bx-1%7D-2x%20%7D%7Bx-7%7D" id=

BARSIC [14]

<h3>Answer: -2</h3>

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Work Shown:

$\displaystyle L = \lim_{x\to\infty} \frac{ \sqrt{x-1}-2x }{ x-7 }\\\\\\\displaystyle L = \lim_{x\to\infty} \frac{ \frac{1}{x}\left(\sqrt{x-1}-2x\right) }{ \frac{1}{x}\left(x-7\right) }\\\\\\\displaystyle L = \lim_{x\to\infty} \frac{ \frac{1}{x}*\sqrt{x-1}-\frac{1}{x}*2x }{ \frac{1}{x}*x-\frac{1}{x}*7 }\\\\\\$

$\displaystyle L = \lim_{x\to\infty} \frac{ \sqrt{\frac{1}{x^2}}*\sqrt{x-1}-2 }{ 1-\frac{7}{x} }\\\\\\\displaystyle L = \lim_{x\to\infty} \frac{ \sqrt{\frac{1}{x^2}*(x-1)}-2 }{ 1-\frac{7}{x} }\\\\\\\displaystyle L = \lim_{x\to\infty} \frac{ \sqrt{\frac{1}{x}-\frac{1}{x^2}}-2 }{ 1-\frac{7}{x} }\\\\\\\displaystyle L = \frac{ \sqrt{0-0}-2 }{ 1-0 }\\\\\\\displaystyle L = \frac{-2}{1}\\\\\\\displaystyle L = -2\\\\\\$

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Explanation:

In the second step, I multiplied top and bottom by 1/x. This divides every term by x. Doing this leaves us with various inner fractions that have the variable in the denominator. Those inner fractions approach 0 as x approaches infinity.

I'm using the rule that

$\displaystyle \lim_{x\to\infty} \frac{1}{x^k} = 0\\\\\\$

where k is some positive real number constant.

Using that rule will simplify the expression greatly to leave us with -2/1 or simply -2 as the answer.

In a sense, the leading terms of the numerator and denominator are -2x and x respectively. They are the largest terms for each, so to speak. As x gets larger, the influence that -2x and x have will greatly diminish the influence of the other terms.

This effectively means,

$\displaystyle L = \lim_{x\to\infty} \frac{ \sqrt{x-1}-2x }{ x-7 } = \lim_{x\to\infty} \frac{ -2x }{ x} = -2\\\\\\$

I recommend making a table of values to see what's going on. Or you can graph the given function to see that it slowly approaches y = -2. Keep in mind that it won't actually reach y = -2 itself.

5 0

2 years ago

What is the solution of the system of equations? -4x+3y=-12 -2x+3y=-18

Kisachek [45]

Answer:

Step-by-step explanation:

I've enclosed a graph to show you that there is one solution.

-4x + 3y = - 12

<u>- 2x + 3y = - 18</u><em><u> </u></em><em> </em>Subtract

-2x = 6 Divide by - 2

-2x/-2 = 6/-2

x = - 3

- 4x + 3y = - 12

-4(-3) + 3y = - 12

12 + 3y = - 12

3y = - 12 - 12

3y = - 24

3y/3 = - 24/3

y = - 8

Which is exactly what the graph shows.

You can tell immediately that this has 1 or more solutions just by looking at the number in front of x and y in each each equation.

It's always a good idea to graph a question like this one. Desmos is a pretty good tool to use if you don't have a graphing calculator.

The y's are the same so you are 1/2 way home in saying what you did.

The x's are different so that means you have at least 1 solution.

7 0

3 years ago